A counterexample to Hedetniemi's conjecture - featuring Erica Klarreich.
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Read Erica Klarreich's Quanta article on this subject: https://www.quantamagazine.org/mathem...

And visit her website: http://www.ericaklarreich.com/

Yaroslav Shitov's breakthrough paper: https://arxiv.org/abs/1905.02167

Thanks to Stephen Hedetniemi for providing us with photos and pages from his original dissertation.

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